currently lots of code manages contexts incorrectly by doing:
```
@dataclasses.dataclass
class WrapCmgr:
_cmgr: ContextManager[T]
def __enter__(self) -> Wrapped[T]:
return wrap(_cmgr.__enter__())
def __exit__(self, \, t: Type[BaseException] | None, v: BaseException, tb:
types.TracebackType) -> bool:
return _cmgr.__exit__(t, v, tb)
```
since https://bugs.python.org/issue44471 using `with WrapCmgr(cmgr()):`
incorrectly raises an AttributeError rather than a TypeError
and https://www.python.org/dev/peps/pep-0343/ still includes this bug, raising
an AttributeError
```
mgr = (EXPR)
exit = type(mgr).__exit__ # Not calling it yet
value = type(mgr).__enter__(mgr)
```
contextlib.ExitStack also had this bug https://bugs.python.org/issue12022
given that it's hard to implement this correctly I think there should be a
builtins.enter and builtins.aenter for use like this:
```
@dataclasses.dataclass
class WrapCmgr:
_cmgr: ContextManager[T]
def __enter__(self) -> Wrapped[T]:
exit, value = enter(self._cmgr)
self.__exit = exit
return wrap(value)
def __exit__(self, \, t: Type[BaseException] | None, v: BaseException, tb:
types.TracebackType) -> bool:
return self.__exit(t, v, tb)
```
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